How to Build a Feature- Frequently Bought Together Products
From the subject, you guys can easily understand what i want to build (similar to Amazon). There are many extensions available (ofcourse they are not free ) to achieve this functionality. But i want to build one on my own; with this i could gain more knowledge and expertise in magento. However, I haven't found any tutorial on this topic. Could any one share with me some tutorial links, if they had one? Also, is it a wise decision to build something which will take enormous time or to buy an extension by spending a hundred of dollars? Any advice?
You can download and learn and enhance according to your functionality, you can even contribute on GitHub for such extensions.
About your question, you should develop or purchase, its up to your situation, urgency and goal. If your purpose is to learn only then you should develop. If you want to see some advanced functionality, you can purchase the extension and see how premium extensions do the code.